De Korte served as the People's Party for Freedom and Democracy campaign manager for the elections of 1972 and 1977.

De Korte became a Member of the House of Representatives after Hans Wiegel was appointed as Deputy Prime Minister and Minister of the Interior in the Cabinet Van Agt–Wiegel following the cabinet formation of 1977, taking office on 22 December 1977 serving as a frontbencher and spokesperson for Economic Affairs and Social Affairs.

De Korte was appointed as Minister of the Interior in the Cabinet Lubbers I following the death of Koos Rietkerk, taking office on 12 March 1986.

The Cabinet Lubbers II fell on 3 May 1989 following a disagreement in the coalition about the increase of tariffs and excises and continued to serve in a demissionary capacity.

[1] De Korte served as Vice Chairman of the Supervisory board of the European Investment Bank from 1 September 2001 until 16 January 2012.